The present invention relates generally to automatic power transmission and particularly to a control circuit for shifting the point of downshift to a higher speed to effect a downshift to the next lower speed.
In an automatic power transmission, it is desirable to use the engine as a brake as an aid to the normal braking because its moving parts produce friction. The magnitude of the friction increases as the engine is driven at high speed, and the maximum engine speed is obtained when the transmission gear is at low. It is therefore necessary that the transmission gear must forcibly be shifted to low when the brake pedal is depressed. When the driver wants to decelerate the vehicle, he exercises greatest care by applying brake repeatedly. It is thus necessary that once the brake is applied, the transmission gear be shifted to low and remains there until the braking is completed.